1. Technical Field
The present disclosure relates generally to the field of combustion furnaces and methods of use to produce glass, and more specifically to systems and methods for reducing foam or its impact during manufacture of glass using submerged combustion melters.
2. Background Art
Submerged combustion melting (SCM) involves melting glass batch materials to produce molten glass by passing oxygen, oxygen-air mixtures or air along with a liquid, gaseous fuel, or particulate fuel in the glass batch, directly into a molten pool of glass usually through burners submerged in a glass melt pool. The introduction of high flow rates of oxidant and fuel into the molten glass, and the expansion of the gases cause rapid melting of the glass batch and much turbulence.
One drawback to submerged combustion is the tendency of the molten glass to foam. The foam may stabilize in a top layer when the molten mass is routed through conventional conditioning and/or distribution channels/systems downstream of the submerged combustion melter. The foam layer may impede the ability to apply heat to the glass using combustion burners to achieve or maintain temperature and compositional homogeneity of the molten glass, and may also impede the rate at which further bubbles in the melt rise and thus effect expulsion of the bubbles and mass flow rate of the melt in the channels. In extreme cases, the foam generated may interfere with the traditional energy application methods employed, which may cause systems to require shutdown, maintenance and may result in a process upset. Attempts to reduce the foam problem through process adjustments have not met with complete success in reducing foam to an acceptable amount.
It would be an advance in the glass manufacturing art if foam could be reduced, or the effect of the foam reduced, during conditioning of molten glass manufactured using a submerged combustion melter and methods.